His exposition is devoted instead to two major themes. He deals, first, with the complicated social struggles in fifteenth-century Spain that created the historical situation in which the Holy Office was set up. This is an absorbing story, well told, though readers unfamiliar with the subject may occasionally get lost in the intricacies of late medieval politics. Secondly, he analyzes in detail and at length the controversies of the period in which the participants debated the beliefs, status, and culture of
the conversos. The central actors in his story are the conversos, or, as he usually calls them, the Marranos. We follow their history from the massacres of the year 1391, when many Jews turned Christian, to the civil conflicts between conversos and other Christians in Toledo and other Castilian cities in the 1440s. The main argument Netanyahu presents can be summarized, in simplified form, as follows.

By the latter part of the fifteenth century, the conversos of Spain -- numbering, at my own rough estimate, perhaps 100,000 people -- had become sincere Christians, quite distinct from the approximately 80,000 Jews who identified themselves as such. They had chosen, voluntarily or not, to convert during the years of persecution at the end of the fourteenth century. Three generations later they were fully fledged, genuine Christians, many of them occupying high political posts in the cities and in
the royal governments of Aragon and Castile. Their conversion to Christianity was often called into question by political opponents. But leading controversialists, including a cardinal in Rome and the leader of a great religious order in Castile, defended the genuineness of their beliefs.

Most convincingly of all, many Jewish rabbis, mainly in North Africa, who were consulted on the question of how Jews should treat conversos, ruled firmly that they were real Christians and in no way secret Jews. The rabbis could not possibly have taken this view if they and other Jews suspected that the conversos were their brethren. Right down to the time of the Inquisition, eminent converso Christians, including prominent members of the administration of Ferdinand and Isabella, strongly asserted the Christianity
of their people. There were occasional cases of judaizing, but the mass of conversos in Spain were Christians. (Indeed, after the conversos were persecuted under the Inquisition, the Jewish writings of the time, Netanyahu comments, contain "cold-blooded assertions that the Marranos got their due, an open manifestation of glee over their 'fall.' ")

These conclusions, which are central to Netanyahu's entire argument, seem to me wholly convincing. By coincidence, they are also the conclusions of another recently published study on the subject, by Professor Norman Roth of the University of Wisconsin-Madison. If we accept them as correct, however, they raise a central question. Why, if there was no problem resulting from the judaizing of conversos, was the Inquisition created? If there were in fact no heretics, why invent a court to bring them to trial?

Netanyahu writes that three main factors led to the creation of the dreaded tribunal. First, by their exceptional success in public life the conversos provoked widespread enmity. Jews were non-Christians and therefore disqualified from holding public office, even though they had sometimes held other posts such as tax officials and estate administrators. Conversos, by contrast, were eligible for all public positions and honors. During the fifteenth century, conversos and their descendants rose to high office as
administrators, judges, and bishops. Many entered the nobility. In some cities their success provoked continuous rivalry, particularly in Toledo in the 1440s. Their enemies everywhere struggled to eliminate them by accusing them of being secret Jews. A new tribunal was required to deal with those who were accused.

Second, the clashes during the fifteenth century between Old (non-Jewish) Christians and New (converso) Christians, as the two categories were called, gave rise to conflicts over identity. In those conflicts, Netanyahu argues, we can see the birth of racism. Conversos could not be denounced by their enemies as Christians, for that was of course no crime; they were therefore denounced as "Jews." In many cities attempts were made to exclude them from office, and the notion of "blood purity" (limpieza de sangre, in Spanish) was conceived as a doctrine to be used against them; the only pure blood, so the theory went, was Christian. Jewish blood, and by extension converso
blood, was impure. In city after city, statutes were proposed which disqualified people of "impure" blood from entering universities, religious
orders, and city councils.

The most important of these statutes was adopted by the city council of Toledo in 1449, and in subsequent decades other institutions promulgated similar laws. Historians have frequently referred to the existence at this time of a "Marrano problem," by which they mean the alleged tendency of conversos to secretly practice Judaism. Netanyahu disagrees. For him what was in question was "the struggle of the Old Christians to reduce the status of the New." The statutes prescribing blood purity were an important weapon in this struggle. Drawing on his studies of converso practices and writings, Netanyahu adds a very important piece of information to help us understand one aspect of the racism of the time. He points out that many of the Marranos, long after their conversion, continued to look on themselves as a "nation," separate from Jews as well as Old Christians. "The Marranos," he writes,

were viewed as a distinct nationality which, in more ways than one, was related to the Jews. Indeed, not only did their enemies so regard them, but also their friends among the Old Christians; and, what is more, they were so regarded by the Marranos themselves. The latter, who insisted that religiously they were Christians and had nothing to do with Judaism and its followers, could not help admitting their actual belonging to a separate entity, which they clearly defined.

This, obviously, created a special identity which marked them out from others and fostered racism.

Third, the crown, in the person of King Ferdinand "the Catholic," decided to fortify its weak political position by allying itself with anti-converso forces. Neither the king nor Queen Isabella was anti-Semitic. They had been friendly toward individual conversos and Jews and they would continue to be so. But their political strategy turned them against conversos generally. Traditionally, Jewish historians have identified Isabella as the malign influence. Netanyahu, by contrast, sees Ferdinand as the dominant partner,
and he is unsparing in his characterization of him. Ferdinand is, for him, the real founder of the Inquisition. He did not establish the Holy Office for any religious reason; nor, as some have claimed, was it primarily his intention to prey on the accumulated wealth of the conversos. Robbery was only the incidental consequence of his anti-converso policy, not its main purpose. Ferdinand's motive was straightforward Realpolitik, an attempt to form an advantageous alliance.

These arguments are set out magisterially by Netanyahu in a smoothly linked narrative that combines scholarly evidence, careful reasoning, and passionate rhetoric. A reader with some knowledge of the history of the Inquisition might well ask: What of the thousands of cases which document the judaizing activities of the conversos? Do they not demonstrate that the inquisitors were responding to what they saw as a religious problem?

The archives of the Holy Office are among the richest sources of information available anywhere to historians. Carefully preserved by the inquisitorial bureaucracy, they offer minute detail not only on court cases but also on the private lives and practices of thousands of ordinary men and women who appeared before the judges. The papers of the Roman Inquisition are still not available for examination. But those of the Spanish Inquisition, housed in the national archive in Madrid, have for some time been available to
researchers. Henry Charles Lea and all other subsequent historians of the Holy Office have relied on them. So, too, have many Jewish historians. All of them have given full credence to the trial documents, but for differing reasons. The Jewish scholars, led by Baer, accepted the evidence of the documents because they demonstrated that the conversos were indeed heretics, and therefore at heart belonged to Israel. Ironically, then, these historians accepted that there was some justification for the Inquisition.

But who in his right mind, Netanyahu would ask, could accept as reliable, without separate corroborating evidence, the documents used by a secret police organization as evidence for prosecution? And who could accept such papers as justifying the existence of that police? Yet this, in his view, is what scholars of the Inquisition have done. Not surprisingly, some other historians have had doubts about the truth of the Inquisition documents. Netanyahu rejects them as unreliable, but he does not claim that they are
complete inventions. Virtually all the documents refer, he points out, to judaizing after the formation of the Holy Office. Before that date, he writes (and here the facts certainly support him), there is no reliable evidence of a judaizing movement on a scale to warrant the creation of a special judicial tribunal.

Marrano leaders and Jewish leaders said again and again that the New Christians were indeed Christians. "If this was the state of Judaism among the Marranos," writes Netanyahu, "the claim that the Inquisition was established to suppress a widespread crypto-Jewish movement in their midst must be regarded as untrue." Of course, he says, evidence of judaizing was produced after the Inquisition was established. But this was because many of the despairing, persecuted, New Christians reverted in their misery to the old faith. It was not the judaizing of the Marranos that produced the Inquisition, but the Inquisition that produced the judaizing of the Marranos.

Up to this point Netanyahu's argument makes sense. If it is generally accepted by historians, it must point Inquisition studies in a new direction and revolutionize our approach to the study of Spanish Jewry. The reasons he puts forward for the founding of the Inquisition must, however, be approached with considerable care. Spain's history in the fifteenth century has not been extensively studied, and the documentation is sparse. Netanyahu's three central arguments are entirely plausible but also raise difficulties that invite debate.